用C# GDI 绘制一张精美的分享二维码图片

简单干脆，直接上代码

 var key = "http://www.xxx.xyz";
            int width = 400;
            int height = 400;
            int pointX = 100;
            int pointY = 150;
            //绘制 二维码
            EncodingOptions options = new QrCodeEncodingOptions()
            {
                DisableECI = true,
                CharacterSet = "UTF-8",
                Width = width,
                Height = height,
                Margin = 1,
            };
            BarcodeWriter writer = new BarcodeWriter();
            writer.Format = BarcodeFormat.QR_CODE;
            writer.Options = options;
            //二维码图片
            Bitmap bitmap = writer.Write(key);

            //背景 我暂时用白底的位图
            Bitmap b1 = new Bitmap(600, 700);
            Graphics g1 = Graphics.FromImage(b1); //创建g1的Graphics
            g1.FillRectangle(Brushes.White, new Rectangle(0, 0, 600, 700));
            g1.DrawImage(bitmap, pointX, pointY, width, height);

          
            string avatar = "http://img.yohao.xyz//images/181019235249.jpeg";
            //从链接地址中获取图片
            Image avatarImage = ImageFromWebUrl(avatar);
            //将头像圆形处理 
            var avatarBitmap = CirclePhoto(avatarImage, 100);
            //绘制头像
            g1.DrawImage(avatarBitmap, 40, 40, 100, 100);

            var emSize = 20F;
            var nickName = "我是一个优雅的小码弄";
            SolidBrush solidBrush = new SolidBrush(Color.CadetBlue);
            //绘制名称
            g1.DrawString(nickName, new Font("黑体", emSize), solidBrush, new PointF(150, 60));

            //画底部文字
            var tip1 = "躺着也能赚钱的购物商城";
            var tip2 = "扫一扫上面的二维码进入商城";

            StringFormat sf = new StringFormat();
            sf.Alignment = StringAlignment.Center;
            g1.DrawString(tip1, new Font("黑体", 18F), new SolidBrush(Color.FromArgb(86,78,78)), new PointF(300, 570), sf);
            g1.DrawString(tip2, new Font("黑体", 18F), new SolidBrush(Color.FromArgb(86, 78, 78)), new PointF(300, 610), sf);
            g1.Dispose();
            byte[] imgByte = BitmapToBytes(b1);
            var resp = new HttpResponseMessage(HttpStatusCode.OK)
            {
                Content = new ByteArrayContent(imgByte)
            };
            resp.Content.Headers.ContentType = new MediaTypeHeaderValue("image/jpg");
            return resp;

这里我是用webapi 写的 直接返回一张图片。

下面附带上面用到的一些方法

• 从Bitmap转换成 byte[]

  public byte[] BitmapToBytes(Bitmap Bitmap)
       {
           MemoryStream ms = new MemoryStream();
           Bitmap.Save(ms, System.Drawing.Imaging.ImageFormat.Bmp);
           byte[] bytes = ms.GetBuffer(); 
           ms.Close();
           return bytes;
       }

• 从url中获取Steam

  public Stream StreamFromWebUrl(string url)
       {
           WebRequest webRequest = WebRequest.Create(url);
           HttpWebRequest request = webRequest as HttpWebRequest;
           HttpWebResponse response = (HttpWebResponse)request.GetResponse();
           string encoding = response.ContentEncoding;
           return response.GetResponseStream();
       }

-从url中获取Image

  	  /// 

      /// 从url中获取Image
      /// 
      /// 
      /// 
      public Image ImageFromWebUrl(string url)
      {
          Stream sm = StreamFromWebUrl(url);
          return Image.FromStream(sm);
      }

-将图片转换层圆形

 /// 

      /// 将图片转换层圆形
      /// 
      /// Image 图片
      /// 图片的尺寸
      /// 
      public Bitmap CirclePhoto(Image file, int size)
      {
          using (Image i = file)
          {
              Bitmap b = new Bitmap(size, size);
              using (Graphics g = Graphics.FromImage(b))
              {
                  g.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.HighQuality;
                  g.DrawImage(i, 0, 0, b.Width, b.Height);
                  int r = Math.Min(b.Width, b.Height) / 2;
                  PointF c = new PointF(b.Width / 2.0F, b.Height / 2.0F);
                  for (int h = 0; h < b.Height; h++)
                      for (int w = 0; w < b.Width; w++)
                          if ((int)Math.Pow(r, 2) < ((int)Math.Pow(w * 1.0 - c.X, 2) + (int)Math.Pow(h * 1.0 - c.Y, 2)))
                          {
                              b.SetPixel(w, h, Color.Transparent);
                          }
                  //画背景色圆
                  using (Pen p = new Pen(System.Drawing.SystemColors.Control))
                      g.DrawEllipse(p, 0, 0, b.Width, b.Height);
              }
              return b;
          }
      }

最后附带 最终生成效果